Lewis & Short

mellīgo, ĭnis, f. [mel].

  1. I. A honey-like juice, sucked by the bees from flowers, but not yet made into honey, bee-glue, bees’rosin, hive-dross (post-Aug.), Plin. 11, 6, 5, § 14; 16, 7, 10, § 28.
  2. II. The juice of unripe grapes: uvae, Plin. 12, 27, 60, § 131.